Escapement device on paper carriages for typewriters



NW; 23, 1937. F. EHBERT 2,100,071

ESCAPEMENT DEVICE ON PAPER CARRIAGES FOR TYPEWRITERS Filed April'l9, 1933 QCLQYMU ATTORNEY UNITED STATES PATENT o FFicE 1 ESCAPEMENT DEVICE ON PAPER CAR- RIAGES FOR 'TYPEWRITERS Fritz Eibert, Munich, Germany, assignor to Robert Wolff, Basel, Switzerland Application April 19, 1933, Serial No. 666,794

In Germany April 26, 1932 3 Claims.

The present invention relates to an escapement device for typewriters, and more particularly to an improved escapement device which receives I its energy from the carriage spring rather than carrier etc., are coupled together with the paper carriage escapement in such away that the expenditure of force required for their movement is supplied by the operator of the machine by himself when striking each single key; the movement of all these different parts causing a significant 15 increase in the force applied when striking each 1 key.

Itis an object of the present invention to provide an escapement device for typewriters which enables the stroke on thekeys to be as light as possible. V V

. It is another object of the present invention to provide means whereby the keys are arranged as V triggers which set the escapement device and the type levers in motion under the energy from the carriage spring. 7

It is a further object of the present invention to provide an escapement device which will quicken the return movement of the type lever under the energy originally supplied by the carriage.

It is also within the contemplation to provide an escapement device adapted to eliminate the recoil springs on prior escapement devices and the type levers which springs require a greater amount of force to operate the keys.

Other objects and advantages will become apparent from the following description taken in conjunction with the drawing in which:--

Fig. 1 illustrates a'plan view of a universalbar having two integral pawls, embodying the present invention;

Fig. 2 depicts a front view of the universal bar shown in Fig. 1.. r

.In the drawing, I represents the detainer, 2 the' displacement pawl, hereinafter called the transverse bar, 4 the tooth of a ratchet wheel, and 3 the universal bar common to all type-levers of the machine.

The action of the construction shown in Figures 1 and 2 is as follows. It is presumed that the tooth 4 of the ratchet wheel for which a rod,

roller and similar arrangement can be used, rests on the sliding surface of the detainer I. Theuniversal bar 3 and the detainer l are brought into 55 the position shown in broken lines in Figure 1 -when the type-lever is forced downwards by a touch on the key. At this 'moment,'the transverse bar 2 comes into contact with the tooth 4 of the ratchet wheel. Under the action of the return spring, on the carriage (not shown), the 5 tooth slides along the inclined surface of the transverse bar 2 which returns the universal bar 3 to its initial position. As is seen in Figure 1, the detainer I, during the forward movement of the universal bar, i. e., during its transport to the position shown in broken lines, liberates the tooth 4, which tooth then at once touches the transverse bar 2 lying in the path of the tooth 4. Without the necessity of special springs, and merely by the sliding movement of the tooth 4 against the transverse bar 2 the universal bar 3 is pushed back to the full extent of the forward movement into its initial position. The next tooth of the ratchet wheel is then detained or held fast by the detainer I.

What I claim is:-

1. In an escapement device for the paper carriage of typewriters, the combination comprising a powered ratchet wheel having teeth, a universal bar actuated by a key lever of said typewriter, a flat and plate-like detaining pawl rigidly mounted on said universal bar vertically to u the direction of movement of said ratchet wheel teeth, a plate-like displacement pawl mounted on said universal bar at an angle to said detaining pawlv whereby a tooth of said ratchet wheel will be engaged and retained by said detaining pawl in the normal position of rest of said universal bar, and said tooth will be released in a triggerlike manner and will slideably engage said displacement pawl and return said pawls and said universal bar into its initial position of rest after actuation of said bar'by a key lever of said typewriter.

2. In an escapement device for typewriters, the 4 combination which comprises a powered ratchet I wheel having a plurality of teeth, a universal bar actuated by a key lever of said typewriter, a flat and plate-like detaining pawl integral with said universal 'bar and engaging one ratchet wheel tooth at a time, a flat and plate-like displacement pawl integral with said universal bar and having a working surface at such angle to the path of said teeth that a tooth disengaged by said detaining pawl slides along the angle surface of said displacement pawl and guides the universal bar back to its initial position of rest where the detaining pawl engages the next succeeding tooth.

3. In an escapement device for typewriters 55 which comprises a universal bar actuated by a key lever of said typewriter, a flat and plate-like having a toothed ratchet wheel, the improvement.

and to release said tooth in a trigger-like manner on actuation of said universal bar whereby said disengaged tooth will slide along the inclinedsurface of said displacement pawl and will guide the said universal bar back to its initial position of rest where the detaining pawl engages the' next succeeding tooth.

' FRITZ EIBER'I. 

